Knife rocking mechanism for veneer cutting machines



Nov. 24, 1942. F. KOSSHIR KNIFE ROCKING MECHANISM FOR VENEER CUTTING MACHINES Filed Dec. 23, 1940 5 Sheets-Sheet 1 HTrOP/VL'YJ.

Nov. 24, 1942. I L. F. Koss, JR 2,303,213

KNIFE ROGKING MECHANISM FOR VENEER CUTTING MACHINES Filed Dec. 25, 1940 5 Sheets-Sheet 2 7 I/vvE/v roe, Lou/s F A OJJ, J22,

g T TOPNE vs P 24, 1942- L. F. KOSS, JR v ,30

KNIFE ROCKING MECHANISM FOR VENEER CUTTING MACHINES Filed Dec. 25, 1-940 5 Sheets-Sheet 3 a \z a & 1 3 0 s u "an Q NOV. 24, 194-2. 055, JR 2,303,213

KNIFE ROCKING MECHANISM FOR VENEER CUTTING MACHINES Filed Dec. 23, 1940 5 Sheets-Sheet 4 INVENTOE, Lou/.51: hoas; J22, Er W I Nov. 24, 1942. L. F. Koss; JR

KNIFE ROCKING MECHANISM FOR VENEER CUTTING MACHINES 5 Sheets-Sheet 5 Fii ed Dec.

IIIIIIIII- VIIIIIIIIII IIIIIIIIIIII III I I NYE/V7019, Log/5 f. A OJJ, k/, 15v Wm M Patented Nov. 24, 1942 UNITED STATES PATENT OFFICE ROCKING MECHANISM FOR VENEER CUTTING MACHINES Louis F. Koss, Jr., Indianapolis, Ind., assignor to Capital Machine Company, Indianapolis, Ind., a corporation of Indiana Application December 23, 1940, Serial No. 371,311

3 Claims.

This invention relates to means for automatically rocking the cutting knife in a veneer slicing machine in timed sequence with the vertical travel of the fiitch. It is the usual practice to pull the fiitch diagonally downwardly over the knife and then to rock the knife back away from the fiitch as the fiitch is raised for the next succeeding cut. This shifting of the knife has heretofore been accomplished by a. rather complicated system of levers-which introduced a plurality of joints or bearings permitting, following a slight wear in each of those bearings, inaccuracy in thickness of cut of the veneer since'the knife would not always be rocked back to the correct position. For certain work, it is necessary to maintain the thickness of the veneer sheet within an accuracy of but a very few thousandths of an inch.

The present invention has, as its primary advantage, an extremely accurate control of the repositioning of the cutting knife so that the sheet of veneer cut may be uniformly held within the required degree of tolerance. In order to accomplish that result, the invention provides a structure having the minimum number of points of wear in the control of the rocking of the knife holder. A still further important advantage of the invention is found in the fact that the degree of rocking of the knife may be held within very close predetermined limits, all Without any critical adjustments. These and many other objects and advantages of the invention will become apparent to those versed in the art in the following description of one particular form of the invention as applied to a well known type of veneer slicing machine, as illustrated in the accompanying drawings, in which Fig. 1 is a view in end elevation of a machine to which the invention is applied;

Fig. 2, a view in transverse vertical section on the line 2-2 in Fig. 1;

Fig. 3, a view in rear elevation of the machine;

Fig. 4, a detail on an enlarged scale in perspective of the actuating and control mechanism as applied to the veneer cutting machine;

Fig. 5, a diagrammatic representation of'the control mechanism in vertical section; and

Fig. 6, a view in vertical section on the line 6-6 in Fig. 5.

Like characters of reference indicate like parts throughout the several views in the drawings.

Referring to the drawings, the machine to which the invention is applied is driven in the customary manner by an electric motor i carryknown manner.

l2 in turn, through a shaft l3, driving the gears l4 and I5, to, in turn, drive the connecting rods I6 and I1 respectively, that are attached to the vertical fiitch table l8, all in the usual and well As indicated, this table I8 is slidingly mounted on the three inclined, parallel guide frames 19, 20, and 2| whereby the table i8 is carried to the right, Fig. 3, as it is lifted toward the top of those members.

These frame members 19, 20, and 2| are suitably mounted in the usual manner on a bed frame 22 which frame, having separate cross members, extends on beyond the frame members to carry the carriage 23 that is advanced toward and away from the table l8 along that bed frame in the usual and well known manner, herein indicated as by the screws 24 and 25 operating from the ratchet mechanism 26, Fig. 3. The carriage 23 supports, through suitable framework 21, the cutter knife 28 at the forward end thereof. The framework 21 is pivoted at its lower front portion on a steel bearing pin 29 at each end in such manner that the frame 27 may be rockedon the carriage 23 to tilt the upper end of the knife 28 toward and away from the table I8, Fig.

1. The machine thus far described, as above indicated, is selected as one to which the present invention may be applied, the description so far relating to a machine heretofore in commercial usage.

Obviously the frame 21 with its veneer receiving table 30, knife 28, and other attendant members, necessarily is of considerable weight. Ad-- vantage is taken of this weight to normally rei turn the frame 21 to a position winging the cutting edge of the knife 28 away from the fiitch table l8. This is the position in which the knife 28 is maintained during the upward travel of the table i8 so that the knife will not drag over the fiitch in that upward stroke. Then, of course, at the upper end of that stroke of the table l8, the knife 28 must be swung back into a very definite position in relation to the fiitch for cutting the sheet of veneer as the table l8 travels downwardly. It is to be understood, of course, that the fiitch (not shown) is secured to the table I I8 on its rear face thereof by dogs 3| in the usual and well known manner. The description of the mechanism forming the invention and accombearing 32 and 33, Fig. 2. On the top of each of in a pinion gear H meshing t larger ar thesebearings is slidingly positioned a cross head- 34 and 35 respectively. These two cross heads 34 and 35 are rigidly tied together by an intervening T-iron 36, herein shown as being bolted to the heads. The length of the iron 36 is made to be such that, as indicated in Fig. 2, the heads 34 and 35 may travel as a unit with the iron 36 between the side members of the carriage 23. In the form herein shown, the bearings 32 and 33, as indicated in Fig. 6, the bearing 33 being a duplicate of the bearing 32, each has a slot formed in its upper side to guide the cross head resting thereon so as to prevent fore and aft travel and confine the travel to a transverse direction, that is, transverse of the carriage 23. The upper portion of the cross head 34 has a bore entering from its top face to terminate by a spherical bottom face.

A pin 31 is formed to haveball-shaped ends, one of which ends is dropped into the bore in the cross head 34 to seat against the spherical end of that bore. The pin 31 is entered by its upper ball end into a socket formed within a block 38, Figs. 2 and 5. This block 38 has a stem 39 screw-threadedly engaging with and passing through a foot 49 that extends from the knife bar frame 21 directly over the cross head bearing 32. This block 38 may be raised and lowered in relation to the foot 40 by turning the stem 39 in relation to the foot 49 by any suitable means, such as by the squared upper end 4|, following which adjustment the stem 39 may be locked in position by any suitable means, such as the jam nut 42 screw-threadedly engaged with the stem 39.

In the same manner a pin 43 rests by its lower end on the cross head 35 and has its upper end received within the block 44 carrying a stem 45 screw-threadedly passing through the foot 46 extending from the frame 21. The pin 43 is a duplicate of the pin 31.

Thus it is to be seen that by shifting the cross heads 34 and 35 on their respective bearings 32 and 33, the pins 31 and 43 may be shifted from the vertical positions, as indicated in Fig. 2, to inclined positions as indicated by the one pin 31 in Fig. 5, and thereby effect a lowering of the rear side of the frame 21 to cause a corresponding rocking of the knife 28 away from the table 8. Reversing the travel of the cross heads 34 and 35 will bring the pins 31, 43 back to their vertically aligned positions and thereby lift the rear side of the frame 21 to throw the knife 28 toward the table l8.

To bring about this reciprocating action of the cross heads as above indicated, a piston rod 41 is secured to one of the cross heads, herein shown as the cross head 34, by any suitable manner, such as by screw-threadedly engaging the end of the rod 41 within the cross head 34, Fig. 5. The piston rod 41 is carried outwardly through the side member of the carriage 23, Fig. 5, with ample clearance therethrough to permit horizontal reciprocation of the rod. The rod extends on outwardly beyond the carriage 23 to enter within a cylinder 48 to be attached to a piston 49 therein.

The cylinder 48 is formed to have a sufiicient length to permit travel of the piston 49 therein in excess of the amount of travel required for rocking the pins 31, 43. To limit the travel of the piston rod 4? to the required amount, a suitable stop, such as a nut 56, is fixed on the piston rod 41 outside of the carriage 23 by any suitable means, preferably permitting axial adjustment along the rod 41.. In the form herein shown,

this nut 50 takes on the character of a disc and its connection with the rod 41 is by means of screw-threads. Surrounding the rod 41 and interposed between the nut 50 and the side member of the frame 23 is a resilient cushion block 5| made out of any suitable material, such as rubber or the like. The nut 59, by suitable adjustment, will limit travel of the piston rod 41 to the right, Fig. 5. To limit travel in the reverse direction, reference is made to Fig. 2 to a stop rod 52 that is fixed by its inner end to the cross head 35 and extends outwardly through the side member of the carriage 23 to have mounted on that outer portion a stop nut 53 fixed in position by a jam nut 54 screw-threadedly engaging with the rod 52. Preferably a bumper block 55 similar to the block 5| is interposed between the outer side of the carriage 23 and the stop 53 as a cushion. Thus it is to be seen that by suitably adjusting the members 56 and 55 in relation to the position of the piston 49 in its cylinder 48 and in relation to the angularity desired of the pins 31, 43, it is to be seen that the combined travel of the cross heads 34, 35 may be kept within the limits desired.

The cylinder 48 is provided with the outer and inner heads 56 and 51, through each of which leads a single passageway 58 and 59 respectively. The inner head 51 is supported from the carriage 23 by any suitable manner, such as by the bolts 60, to hold the cylinder 48 in axial alignment With the piston rod 41. From the outer head passageway 58 leads a pipe 6| having a part of its length at least consisting of a flexible hose to provide for travel of the carriage along the bed 22. This pipe BI is connected through a suitable fitting 62, herein shown as a T, with a passageway 63, Fig. 5, formed in the head 64 on a cylinder 65. This cylinder 65 is mounted on the frame member 2|, Figs. 3 and 4.

From the other passageway 59 in the inner head 51 on the cylinder 48, Fig. 5, extends a pipe line 66 also having a part of its length at least consisting of a flexible hose. This pipe line 66 is conducted to connect with a passageway 61 formed in the upper head 68 of the cylinder 65. In the form herein shown, this pipe line 66 terminates in a T 69, one outlet of which is connected with the passage 61.

A tank 10 is mounted on the frame member 2| above the cylinder 65 and is arranged to hold a quantity of any suitable fluid, such as oil. The tank is not sealed at its top but preferably has a lid or cover 1| thereover to prevent dust and the like from falling into the tank. A pip line 12, for convenience consisting of a flexible hose, leads from the lower end of the tank 16, here shown as from the side wall near the floor of th tank, downwardly to discharge through a check valve 13. This check valve 13 is, in th present form, shown as having its discharge end connected with a T 14 from one end of which leads a flow line, herein shown as an L 15, connecting with the upper end of the T 62. The check valve 13, as above indicated, is arranged so that it is normally open to allow fiow of the oil from the tank 16 by gravity down into the pipe line 6| and also into the cylinder 65 through the passageway 63. The check valve 13 closes upon up-flow. There is further provided in connection with the pipe line 6| a pressure relief valve 16 connected with the T 14. This relief valve is normally closed but should it be opened by excessive pressure in the pipe line 6|, discharge from the valve 16 is conducted through a line 11 back up into the tank 70. Since both the check valve 13 and the relief valve 16 are of the usual type commercially obtainable, details of their construction are not herein shown.

In lik manner a feed line "leads from the tank 10, Fig. 5, through a check valve 19 and through suitable fittings, such as the T 80, L 8| and pipe 82 into the T 69 to permit flow of the oil from the tank 18 into both the pipe line 66 and the cylinder 65. The check valve 19, like the valve 73, is normally open in the absence of pressur in the line 66 but closes upon the appearance of pressure therein. The line 66 is provided with a relief valve 83 that is normally closed and Opens only upon a predetermined excessiv pressure being reached in the line 66. Discharge from the relief valve 83 is had through the line 84 directly back into the tank 18.

Within the cylinder 65 is placed a piston 85 connected to a piston rod 86 that extends upwardly through the cylinder head 68 to be guided by its upper end through a bearin 81 mounted on the frame member 2|, Fig. 4. This rod 86 is provided with a pair of spaced apart stop collars 88 and 89, each adjustably secured longitudinally along the rod 86. Carried by the table I8 is an arm 98, Fig. 4, that extends rearwardly from the table to have an end closely surrounding in part at least the rod 86 between th collars 88 and 89. The collars 88 and 89 are properly adjusted on the rod 86 to be alternately contacted by the arm 90 as the table I8 is lowered and raised.

When the arm 96 comes into contact with the lower collar 88, it pushes the rod 86 down to lower the piston 85 in the cylinder 65. In like manner when the table is lifted and approaches the upper limit of its travel, the arm- 90 comes into contact with the collar 89 to lift the rod 85 and thereby lift the piston 85 Within the cylinder 65. Thus it is to be seen that in timed sequence with the travel of the table E8, the piston 85 is reciprocated in the cylinder 65.

Referring now to Fig. 5, when the table l8 approaches its lower limit of travel after having the sheet of veneer cut from the fiitch carried onto the table, the arm 90, upon striking the collar 88, will carry the rod 86 on down to position the piston 85 somewhere within the cylinder 65 as indicated. As the piston 85 travels downwardly, oil having flowed from the tank from the pipe pine 12, check valve 13, T 14, L 15, T 62, passageway 63, pipe line 6!, and into the operating cylinder 48, will be pushed downwardly within the cylinder 65 to cause th oil to travel through the line 6| with sufficient pressure to force the piston 49 to some such position as indicated in the drawing, whereby the cross heads 34 and 35 will be carried to the right and thereby rock the pins 3'! and 43 out of their initially substantially vertical alignment, and thus lower the rear end of the knif frame 21 to rock the knife 28 backwardly away from the flitch. This pressure thus introduced in the pipe line 6| and cylinder 48 by downward travel of the piston 85 is maintained therein since the oil cannot flow back up through the check valve 13 and the relief valve 16 being closed against flow therethrough from normal operating pressures.

The knife frame 21 remains in that rocked position until the table it travels upwardly and approaches its upper end of travel. Just before reaching that end of travel, the arm 90 will strike the collar 89 to have the rod 86 lifted with fur ther travel of the table I8 and thereby pull the piston 85 upwardly within its cylinder 65. This upward travel in the form herein shown, Fig. 5, will carry oil out of the cylinder 65 above the piston under pressure created by that piston travel and will flow through the pipe line 66, through the inner cylinder head 51, against the piston 49, and push it outwardly in the cylinder 48, and thereby in turn, cause the pins 31 and. 43 to be rocked back toward their vertical positions so that the knife 28 is again rocked toward the table [8 into cutting position for the subsequent down travel of the table I8. In this flow of oil out of the upper end of the cylinder 65, it is to be seen that by reason of the check valve 19 being closed upon up-flow or upon pressure being created in the line 66 and by reason of the relief valve 83 normally remaining closed against operating pressures, the flow of oil from the top of the cylinder 65 will be confined to fiow into the cylin-. der 48 to move the piston 49 back toward the lift end thereof, Fig. 5.

By reason of the connecting lines 12 and 18 with the tank 10, the oil lines 6| and 66 are always maintained in a filled condition. Further it is to be seen that by inserting the relief valves 16 and 83 into the system, should anything happen to block the rocking action of the knife carrier frame 21, the relief valves will open upon undue pressure being built up under that situation and thereby prevent the breaking of anyof the parts.

It is therefore to be seen that the simple construction and operation of the invention provides the necessary reciprocation of the knife carriage in that the only wearing surfaces involved that would affect the accuracy of the locating of the knife for each cutting operation are found at the ends of the two pins 31 and 43, The final position of the knife for its cutting operation may be very definitely located by adjusting the stems 39 and 45 relative to the feet 40 and 46. The

bearing surfaces on the ends of these pins 31 and 43 are always under compression. The accurate setting of the knife is obtained, of course, when the pins 3'! and 43 approach the vertical. The pins 31 and 43 do not have to be in the exact vertical positions to maintain that accuracy for the reason that a very slight deviation from the vertical will not occasion any appreciable variation in location of the knife for the cutting operation. That is the reason it is possible to employ the resilient stops 5i and 55 in limiting the travel of the cross heads 34 and 35.

While the invention hasherein been shown and described in more or less minute detail, it is entirely obvious that structural changes may be employed without departing from the spirit of the invention, and it is, therefore, desired that the invention not be limited to that precise form beyond the limitations as may be imposed by the following claims. 1

I claim:

1. For a veneer cutting machine having a reciprocating fiitch table, a carriage, and a knife carrier mounted in overbalanced condition on the carriage to rock normally away from the table, the combination of a cross head under said carrier, a cross head bearing fixed in position relative to the carrier, on which bearing said cross head slides horizontally; a pin positioned in axial, and abutting relation between the cross head and the carrier to transmit the overbalanced load of the carrier longitudinally through the pin to said cross head, hydraulic means for reciprocating the cross head to rock said pin toward and away from a substantially vertical position to lift and lower the overbalanced part of said carrier accordingly, and further hydraulic means controlled by travel of said table to actuate said first hydraulic means intimed sequence with reciprocation of said table.

2. For a veneer cutting machine having a reciprocating flitch table, a carriage, and a knife carrier mounted in overbalanced condition on the carriage to rock normally away from the table, the combination of a cross head under said carrier, a cross head bearing fixed in position relative to the carrier, on which bearing said cross head slides horizontally; a pin positioned in axial, end abutting relation between the cross head and the carrier to transmit the overbalanced load of the carrier longitudinally through the pin to said cross head, hydraulic means for reciprocating the cross head to rock said pin toward and away from a substantially vertical position to lift and lower the overbalanced part of said carrier accordingly, and further hydraulic means controlled by travel of said table to actuate said first hydrauliomeans in timed sequence with reciprocation of said table, and stop means limiting travel of said cross head.

3. In a veneer slicing machine, having a reciprocable table, a carriage, a knife bar frame rockably mounted on the carriage to rock downwardly by a rear portion to tilt a knife away from the table, the combination of a pair of spaced apart aligned cross heads, bearings mounted on the carriage under said frame rear portion, on which bearings said cross heads are supported for sliding movement, a pin upported by an end portion on each cross head and extending upwardly to support by an upper end portion said frame rear portion, said pins being substantially parallel and vertically aligned when said frame is in the cutting position, a bar interconnecting said cross heads to maintain said parallel alignment, a cylinder mounted on said carrier, a piston in the cylinder, a rod interconnecting the piston with at least one of said cross heads, stop means limiting travel of the cross heads to the desired degree of rocking said pins from their normal vertical positions, a pump connected with said cylinder, and means for controlling the flow from said pump toward each end of travel of said table.

LOUIS F. KOSS, JR. 

